Sakamoto Shoten: Born in a Land of Leather
Himeji is renowned as a center of leather production. The Ichikawa River, one of the “Five Rivers of Harima”, has long provided the high-quality water essential for tanning and dyeing, and many leather-related manufacturers are clustered around its banks. Sakamoto Shoten, now a new MUSUBU partner of Knot, is also based not far from the Ichikawa.
Welcoming us were the third-generation owner, Hiroshi Sakamoto, and his son, the fourth generation, Yu Sakamoto. We were shown into the company building that combines the finishing workshop, drying and storage rooms, and a showroom.
“Sakamoto Shoten was founded in 1923, and I am the third generation, but our involvement in leather goes back much further. This land has an ancient connection with leather. My predecessor was my wife’s father, and I came in from outside and inherited the family business, but my own family was also engaged in tanning here. Leather has always been a part of our lives.”
Kurozan Leather: “The Black Diamond of Leather” Once Used in the Armor of Elite Warriors
Kurozan leather is a material with urushi lacquer applied to the surface. Raw lacquer is brushed repeatedly onto the raised grain, producing a remarkable, sparkling luster. Its glittering appearance has earned it the name “the black diamond of leather".
“When people think of urushi, they usually picture lacquerware made on wooden or paper bases. But in fact, using cowhide and deerskin for urushi leather has been widespread since the Nara period. Because the surface becomes extremely hard, it was used in the Warring States period for armor and protective gear. Later, in more peaceful times, its decorative qualities were appreciated, and it came to be used for the protective bags that encased lords’ swords during formal sankin-kotai processions, as well as for suits of armor of high artistic value. This tradition continues today in kendo, one of Japan’s national martial arts. It is especially used in high-end armor worn by kendo masters holding ranks such as renshi, kyoshi, and hanshi.”
Despite the distinguished history of Kurozan leather, its limited applications and the highly specialized skills required to produce it have led to a decline in craftsmen. “Today, I believe there may be only three companies left – including ours – that can still make it,” says Hiroshi.
Even so, Hiroshi has pursued uncompromising quality out of pride as an artisan. “Himeji Kurozan”, exclusive to Sakamoto Shoten, is now recognized worldwide as a rare and uniquely original material.
Mastery of Both Tanning and Lacquering
One reason Sakamoto Shoten has been able to create Himeji Kurozan of the highest quality is that they handle the entire process in-house, from tanning to finishing. Remarkably for a small family-run company, they own their own tannery, equipped with four large rotating drums (taiko) used for washing, tanning, and dyeing.
“It’s not as simple as buying leather elsewhere and just applying lacquer. To achieve the ideal finish, you have to pay careful attention from the tanning and dyeing stages, ensuring compatibility with the lacquer. That philosophy has been passed down since the first generation. Our factory is small – just what we need and nothing more.”
Another key factor is the combined expertise in both highly skilled domains – leather tanning and urushi lacquering – and the experience to integrate them.
“Applying lacquer is no easy task, and using leather, an animal-based material, is very different from lacquerware. Only someone who understands both the materials and techniques of tanning and lacquer can create the ideal Himeji Kurozan leather,” he explains.
It takes about three months to complete a piece of Himeji Kurozan, with only around 20 sheets produced per month, highlighting the labor-intensive nature of this material.
Reviving Leather Through Techniques Passed Down to Successors
A close look at Himeji Kurozan reveals its extraordinary character: urushi lacquer layered over the peaks of the natural grain, catching the light and creating a deep, dimensional sheen. The color harmonized between leather and lacquer is also striking.
“Unlike the smooth base of lacquerware, leather has natural grain with its own texture and depth. That interplay of raised and recessed surfaces creates the distinctive contrast of Himeji Kurozan – the lacquered areas are glossy while the uncoated areas are matte, producing contrasting textures. Japan has long cherished the beauty of shadow, as seen in our history of using the lunar calendar and celebrating the moon. I believe that sensibility may be why this leather resonates so deeply.”
The production methods of Himeji Kurozan are closely guarded, handed down orally only to successors and not publicly disclosed. While we observed part of the process, it was difficult as outsiders to grasp the mastery involved. Still, the meticulous care and effort in every step were evident.
“We only use high-quality Japanese wagyu leather. While it’s harder and more difficult to work with than imported leather, the finished texture is far superior. As for lacquer, we use only natural Japanese urushi – never synthetic. It absorbs humidity from the air to harden and develop shine, and the hardening and color change depending on the day’s temperature and humidity, so the process requires constant judgment. Drying indoors also needs careful monitoring. If even one element is off, the ideal finish won’t be achieved. Leather comes from living animals, so we put our energy into the work, respecting each piece’s unique character and bringing it to shine again.”
From International Acclaim to Domestic Prestige
The birth of Himeji Kurozan was thanks not only to Hiroshi’s technical mastery, but also his creativity.
“We never intended to become a large company, but we wanted more people to know the quality of our leather, so we started expanding overseas in the 2010s.”
He developed new color variations beyond the traditional black and vermilion. With this new artistic dimension, Himeji Kurozan gained recognition in the fashion and materials industries in France, Italy, and Hong Kong. The company received numerous prestigious awards, including the Best New Leather Award at Hong Kong APLF, Asia’s largest international leather industry exhibition (2014), and the Leather Handle Award at Première Vision Paris (2016). It also became a supplier to one of the world’s top luxury brands.
This international reputation elevated its standing in Japan, used for bags and shoes for members of the Imperial family and even for the sandals worn by sumo grand champion Hakuho.
Bringing Its Appeal to More People Through Straps
As part of the MUSUBU project connecting Japan and the world through wristwear, Knot has transformed Sakamoto Shoten’s Himeji Kurozan into a watch strap. Although Hiroshi confessed he does not usually wear watches himself – with his work with tanning and lacquering making them impractical – he expressed delight at this long-awaited collaboration.
“I’m truly delighted and moved that our material has been used to create something new. As a watch strap, it becomes something close to people’s daily lives. It’s a wonderful opportunity to let more people discover Himeji Kurozan, and to share the spirit we put into our craft. Nothing could bring us greater joy.”
Himeji Kurozan, Evolving While Staying True to Tradition
For Hiroshi, Himeji Kurozan represents the culmination of his life’s work. Having perfected the craft to the highest specification, he is preparing to hand the reins to his son, Yu.
“I’ve passed on all of my skills to Yu. He’s exploring new initiatives while preserving tradition, and I hope he maintains what must be preserved as a traditional craft while also driving forward new innovations. It’s what they call “fueki ryuko” – preserving the unchanging while embracing the changing. Each generation is shaped by its own inspirations. As for me, I’m not retiring just yet. I’d like to approach Kurozan with more playfulness, and also return to making materials for kendo armor, our original focus. Since this craft has continued from the samurai all the way to the present day, I want to contribute to it in any way I can.”
This passion expressed through Sakamoto Shoten lives on in Knot’s “Himeji Kurozan Leather Strap” – a meeting point of tradition and modern style.
